MAP03: Inter-Base (Eternal Doom)

MAP03: Inter-Base is the third level of Eternal Doom and was designed by Dietmar Westerteicher. You start off in a glass corridor and enter an underground base.

Essentials
You can get the rocket launcher and chaingun on this level. To find the exit, complete each of the skull key areas - red, blue and yellow - and then backtrack to the blue key area. The mysterious tiled wall that would not open before is now gone. Enter the large area revealed and activate the devil-face switch.

Progression hints (in order of level progression):

-When you see the yellow keycard on a raised platform, there is a switch you must flip on the back side of that platform.

-You'll come to a hall with two blue torches to your right at the end of the hall. Press the wall between the torches. Then turn around and press the switch that is revealed. Finally, when the lift raises up, look for a switch through a window and shoot it. This opens a required teleporter up elsewhere in the level.

-When you're able to, run over the gap to the yellow keycard pedestal facing the switch you previously flipped to lower the yellow keycard.

-Behind the blue door there are two switches, one on each side of a raised platform. Continue flipping both until the bottom of that raised platform is completely flat with blue in the center.

-To get the red keycard, jump into the teleporter in the center of the slime pit (don't miss the jump!). Then jump through a side window to the side of the room with the red keycard.

-In the room with the skullkeys, you must pick up all three (one at a time), but may do so in any order. After you pick up each skull, you can lower the bars of the matching color.

Secrets

 * 1) In the hall outside of the super shotgun room with the "x", press on the wall between the two torches to lower it. You will also reveal a switch directly behind you. Press it, then ride the lift up. Quickly look south and shoot the switch. Now continue with the level until you can reach the blue key. When you lower the blue key platform, ride it up to the opening and enter. Follow the secret passage all the way to the megasphere, and boxes of rockets will also appear. This area counts as three secrets. (sector 340)
 * 2) See Secret #1. (sector 341)
 * 3) See Secret #1. (sector 342)
 * 4) After you get the blue key, return to the yellow key room and open the northern compartment in the nukage if you have not done so already. Inside, open the blue door for some steps leading to the U-shaped walkway outside of the starting point, where you will find a megasphere. The area before the steps counts as three secrets. (sector 306)
 * 5) See Secret #4. (sector 307)
 * 6) See Secret #4. (sector 308)
 * 7) Taking the steps up from Secret #4, you will notice a cracked wall in the middle of the curve. Shoot at it and walk through to get a blur artifact. This area counts as two secrets. (sector 358)
 * 8) See Secret #7. (sector 359)
 * 9) On the path accessible by red skull key, take the right path until it rises up, then go to the left path going back down the steps. As you do, the walls at the end of the steps will lower, revealing a compartment with a revenant (two on Ultra-Violence or higher) and a medikit. There is a lighter wall on the east side you can open, revealing a backpack. Taking that reveals a teleporter nearby, so take it to appear back in the hall overlooking the red keycard area. Go north and the wall will lower, revealing a cacodemon (two on Hurt Me Plenty or higher, as well as a baron of Hell on Ultra Violence or higher) and a soul sphere (there will also be a stimpack in this room, but only on Hurt Me Plenty). This area counts as two secrets. (sector 226)
 * 10) See Secret #9. (sector 227)
 * 11) This secret is in an area resembling the starting area of Nucleus, the next map. This secret was included by mistake and is unreachable without cheating. (sector 551)

Bugs
Due to Secret #11, it is only possible to get 90% secrets on this map. Though the area beyond the exit line can be accessed without cheats by means of linedef skipping, and the door to the secret can be opened from this side, it is still too high to reach.

Two variant monsters, a chaingunner meant to appear on hard difficulties (thing 243) and a shotgun guy meant to appear on easy difficulties (thing 447), both appear on hard and are stuck in each other.

When the blue keycard is lowered, untextured sides of the stairs are exposed, manifesting as flat bleeding or halls of mirrors.

A hard difficulty shotgun guy (thing 199) is partially stuck inside a wall and cannot move.

Current records
The records for the map at the Doom Speed Demo Archive are:

The data was last verified in its entirety on December 21, 2021.

Player spawns
This level contains seven spawn points:
 * 1) facing south. (thing 390)
 * 2) facing north-east. (thing 393)
 * 3) facing south. (thing 394)
 * 4) facing south. (thing 395)
 * 5) facing west. (thing 396)
 * 6) facing east. (thing 397)
 * 7) facing south. (thing 398)

Things
This level contains the following numbers of things per skill level: